Azo dyestuffs and process for preparing them



Patented Um. 1s, 1929.

. ERWIN HOFFA, IRWIN THOMA,-AND-HANS HE YNA,

MANY, ASSIGNOBS TO GRASSELLI 'DYES A CORPORATION OF DELAWARE.

or" HOCHST-N-THE-MAIN, GER-\ TUFF CORPORATION, on NEW YORK, N. x,

' azo mrns'rurrs AND rnocnss FOR PREPARING THEM.

No Drawing. Application filed July 11, 1927, Serial No. 205,031, and in Germany July 21, 1926. I

The present invention relates to new azo .dyestufls and to a process of preparing the same.

There are known only a few bases which when coupled in theform of their diazo-compounds with arylides of the 2-hydroxynaph- -thalene-3-carboxylic acid yield dyestuffswhich'satisfy sufiicientl all requirements as regards fastness to kieroiling. We have found that by coupling a 2.5 d1- methyl-4-halogen-1-diazo-benzene in which one of the hydrogen atoms standing in 3 and '6 position is replaced by a further halogen with anarylamide of 2-hydroxynaphthalene- 3-carboxylic acid new azo dyestuffs of the forlowing formula:

I as

,0 1 1 X OH: OH iL-N-aryl M IBQIGW V R wherein one X stands for hydrogen, the other X stands for ahalogen atom, and the term aryl represents an aryl nucleus which does not contain a hydroxy group or a group containing a hydroxyl group as for instance the carboxylic acid group, are obtainable the fastness of which to kier-boilingsurpasses that of any other dyestuffs of this class, in cluding those made from other dichlorinated bases, as for'instance from 2.5-dichloraniline. The components can be coupled either in substance or on the fiber, or in the presence of any of the usual substrata. i

' The following examples illustrate the in vention, but they are not intended to limit .it thereto:

(1) Cotton material is padded in the usual manner with a grounding liquor prepared from 12 kilos of 2-hydroxynaphthalene 3- carboxylic acid 2"-vmethyl-4f-chloro-1"-anilide, 36 liters of caustic soda solution of 34 B., 24 liters of sodium Turkey red oil of 50 per cent strength, 500 liters of hot water, the. whole being made upwith water to 10 O0 liters.

The dyeing is then developed with a diazosolution prepared as follows :-3.8 kilos of 2 5 dimethyl 4 6 dichloro- 1 aniline are mixed, while stirring, with 5.2 liters of hy drochloric acid of 22 B. and some ice-cold water, and to the mixture'are added 1.44 kilos of sodium nitrite dissolved in water. After the diazotization is complete the mass 1s made up with cold water to 1000 liters and neutralized with sodium acetate until it shows a neutral reaction towards congo 1' paper. After washing and soaping at the boil the dyeing shows a bright red tint of good fastness to chlorine and kier-boiling the dyestufl has the probable formula:

The 2 5 dimethyl-4: 6-dichloro-1-aniline (melting point 47C. to 48 C.) can be made by, saponifying the 1-acetyl-amino-2z5-dimethyl-4:6-dichlorobenzene (meltin point 169 C. to 170 0.; cf. Alvin S. Whee erand Mildred. Morse Journal of the American Chemical Society 46, 257 2257 6 Chemi'sches Centralblatt 1925, I, 380, melting point 167 C.) or by 'chlorinating mineral salts of 1- amino-2z 5-dimethylbenzene in organic solvents.

I (2) Cotton material is padded with a grounding liquor prepared from-12 kilos of 2-hydroxynaphthalene-El-carboxylic; acid-'3- naphthylide, 36liters of caustic soda solution of 34 B., 24 liters of sodium Turkey red oil of 50 per cent strength, 500 liters of hot water, the whole being made up with water to 1000 liters.

The dyeing is then developed with a diazosolution prepared as follows 3.8 kilos of 2: 5- dimethyl-3:4-dichloro-1-aniline are mixed, while stirring, with 5.2 liters of hydrochloric acid of22 B. and ice-cold water, and to the mixture are added 1.44'kilos of sodium nitrite dissolved in Water. ,After the diazotization is complete. the Whole is made up with cold water to 1000 liters and neutralized with sodium acetate until the mass shows a neutral reaction towards congo paper. After washing and soaping at the boil the dyeing shows a bluish-red tint of good fastness to chlorine and kier-boiling the dyestufi has the probable formula The QI5-dimethyl-3.4-dichloro-l-aniline has a melting point of 78 C. to 79 0.; itcan be obtained for instance by chlorinating the 2.5-

dimethyl-l-aniline or the 2.5-dimethyl-4 ,iaphthalene-3-carboxylic acid-2'-met-hoxy-1'- anilide alizarin tints are obtained of an excellent. fastness to light. p In the following claims the term un- I hydroxylated laryl is intended to comprise hydroxyl all such aryl nuclei which do not contain a droxyl group as for instance the car oxylic acid group. The aryl nuclei containing a 'hydroxyl group. are to beexcluded from the claims, in so far asthe dyestuffs containing a hydroxylated aryl, nucleus are not fast to kier boiling as s the object of this invention.

We claim: 1. As new products the following formula:

wherein aryl-represents an unhydroxylated azo dyestuffs of the OH OO-NH-aryl aryl nucleus being yellowish-red to bluishred and yellowish-red t-o brownish-red powders and yielding when produced on the fiber dyeings of excellent properties as to fastness. 2. As a new product, the azo dyestufi of the following formula:

Cl CH: OH CO NH 3 2 I O1 4 1 N=N group or a'group containin a hybeing a bluish-red powder and yielding when produced on the fiber a bluish-red dyeing of an excellent fastness as to kier-boiling.

3. As new products the azo dyestuffs of the following formula: v

x cm on 3 2 halogen 4 v 1 N: 5 6 H3O X wherein aryl .represents an unhydroxylated" aryl nucleus one X represents hydrogen andv the other X represents halogen, being yellowish-redto brownish-red and yellowish-red to'bluish-red powders and yieldingwhen produced on the 'fiber dyeings of excellent properties as to fast-ness.

4. As new products the azo dyestuffs of the following formula:

X CH3 OH CO-NH-aryl 3 2 halogen 4 6 1 N=N wherein aryl represents an aryl nucleus of the benzene or naphthalene series which may be substituted by halogen, alkyl or alkoxy, one

X represents hydrogen and the other X represents halogen. v

5. As new products the azo dyestuffs of the following formula:

01 on. on OO-NH-aryI s 2 c1 4 1 N=N wherein aryl represents an aryl nucleus of the benzene o'r naphthalene series which may be substituted by halogen, alkyl or alkoxy.

In testimony whereof, we aflix our signat-ures.

ERWIN HOFFA.

ERWIN' THOMA. HANS HEYNA.

' CERTIFICATE OF CORRECTION.

Patent No. 1,698,884. 7 I Granted January 15, 1929, to

ERWIN HOFFA ET AL.

It is herebycertified that error anpears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 85, after the word "acid" strike out the numeral "'3" and insert instead the Greek letter "B"; page 2, line 17. before the word "naphthylide" strike out the numeral "3" and insert instead the Greek letter "B"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record I of the case in thePatent Office.

Signed and sealed this 19th day of February, A. D. 1929.

. M. J. Moore, (Seal) Acting Conmissioner of Patents. 

